Printer with rectilinear type-carrying belt

ABSTRACT

A printer of the type wherein an endless type-carrying belt moves across the print line of a print-receiving means, wherein a plurality of hammers are disposed along the print line opposite respective printing positions, whrein a selected one of said hammers is actuated when the character on said belt opposite thereto is the character to be printed at that printing position, and wherein means is provided to prevent lateral stresses on said hammers at the moment of printing.

United States Patent Deproux 1 July 8, 1975 PRINTER WITH RECTILINEAR 3,507,213 4/1970 Derc 101/93 C BE T 3,611,922 10/1971 Carroll et a1 101193 C TYPE CARRYING L 3,651,915 3/1972 Folkens [75] Inventor: Jacques Roland Deproux, Sevres, 3.715.978 2/1973 Raid r France 3,760,925 9/1973 Bossi 10l/93 C X [73] Assignee: Honeywell Information Systems Inc.,

waltham, Mass Primary Examiner-Edgar S. Burr Assistant Examiner-Edward M. Coren 1 Filed: 15, 1973 Attorney, Agent, or Firm-William F. White; Ronald 21 Appl. No.2 388,506 Reilins Related US. Application Data Continuation of Ser. No. 249,304, May 1, 1972,

abandoned.

[52] U.S. Cl 101/111; 101/93.14 [51] Int. Cl B41j 1/20 [58] Field of Search 101/93 C, 111; 197/53 [56] References Cited UNITED STATES PATENTS 3,416,442 12/1968 Brown et 101/93 C 3,473,466 lO/l969 Thayer 101/93 C 3,504,623 4/1970 Staller 101/93 C 5 7 ABSTRACT A printer of the type wherein an endless type-carrying belt moves across the print line of a print-receiving means, wherein a plurality of hammers are disposed along the print line opposite respective printing positions, whrein a selected one of said hammers is actuated when the character on said belt opposite thereto is the character to be printed at that printing position, and wherein means is provided to prevent lateral stresses on said hammers at the moment of printing.

9 Claims, 9 Drawing Figures PRINTER WITH RECTILINEAR TYPE-CARRYING BELT This is a continuation of application Ser. No. 249,304, filed May I, 1972, and now abandoned.

BACKGROUND OF THE INVENTION The present invention relates to printers, and more particularly to printers with a linear character support.

Certain types of prior art printers comprise a flexible metallic belt which forms an endless closed loop and bears transverse elastic fingers (for example, cut into such belt) regularly spaced apart along the length of the belt, each finger being provided with a character or symbol at its free extremity. This belt is held between two pulleys and is driven with a motion which causes the characters and symbols thereon to pass in front of a print-receiving means, which, in turn, is disposed parallel to a rectilinear portion of the belt. One such printer further comprises a plurality of aligned striking hammers disposed opposite to the rectilinear portion of the belt. These hammers are mounted in fixed positions, but can be moved perpendicularly to the direction of motion of the characters on the belt, for example, under the action of electromagnetic means. Thus, when the print-receiving means is suitably positioned and when a character to be printed is carried by the belt past the appropriate location on the print-receiving means, the corresponding hammer is actuated to bring such location on the print-receiving means into contact with such character in a manner to print the character image on the print-receiving means.

Printers of this type exhibit a serious defect in that the belt is not halted during the striking of the characters, but continues to pass at high speed in front of the hammers. Consequently, at the time of the striking of the characters, the hammers come into contact with the belt, although only very briefly, and sustain stresses parallel to the direction of motion of the belt because of the motion of the latter. As a result, the apparatus by which these hammers are attached to their support deteriorates rapidly.

Accordingly it is the object of the present invention to remedy these disadvantages of the prior art printers.

SUMMARY OF THE INVENTION In accordance with the present invention, a printer with a linear character support, wherein the characters move in relation to the print-receiving means and wherein a plurality of hammers are mounted at fixed positions and arranged to move perpendicularly to the direction of motion of the characters, is characterized by comprising a plurality ofintermediate'members disposed at fixed positions between the hammers and the characters. Such intermediate members are movable perpendicular to the direction of motion of the characters and are normally held separated therefrom, each of such members being associated with one of the hammers.

Thus, at the moment of the striking of the characters, it is the corresponding intermediate members which sustain the lateral stresses due to the movement of the characters.

The supporting apparatus for such an intermediate member may be formed of a single elastic leaf whose length is substantially perpendicular to the direction of motion of such member and which bears the member at its free end.

If the print hammers are very close to one another, the strength of these elastic leafs may be enhanced if they are made wider at their edges opposite to the edges at which the intermediate members are attached. In such instance. the adjacent leafs partially overlap each other at their anchored edges.

According to one variation of the invention, the supporting apparatus for an intermediate member is formed of two elastic leafs whose length is substantially perpendicular to the direction of motion of the member and which hold the member between them at their free ends.

In order to increase the strength of such supporting apparatus, it is preferable that the two leafs thereof be formed so that their legs for anchoring the apparatus to the printer structure be separated from one another. Furthermore, it is advantageous, with respect to the elasticity of such an apparatus, that the two elastic leafs be shaped so that their middle portions are coplanar.

Preferably, in order to obtain simultaneously, in a simple and economical manner, a supporting set for all of the intermediate members and to facilitate the mounting thereof, one such set is composed of two groups of the last mentioned leafs, each such group comprising all of the elastic leafs disposed on one side of the intermediate members. The leafs of a group are attached to one another in the vicinity of their anchoring legs. Each of these groups of leafs may be obtained by cutting it from an elastic metallic strip. Preferably, the two groups of leafs are identical, but inverted by relative to one another.

Clearly, in order to prevent these elastic supporting apparatuses from continuing to vibrate after having been struck by the hammers, it is necessary that the critical frequency of the supporting apparatus for an intermediate member be greater than that of the associated hammer, Furthermore, such a supporting apparatus must not be so stiff as to absorb too great a portion of the energy which is communicated thereto by the hammer, or so limp as to not return rapidly to its initial position. Preferably, these supporting apparatus are formed of titanium.

The intermediate members may have a mass negligible in relation to that of the striking hammers and continuously be held flat against the corresponding hammers, under the action of the elastic leafs.

Conversely, the intermediate members may have a mass not negligible in relation to that of the striking hammers and constantly be held separated, except for the moment ofa striking, from the corresponding hammers, by virtue of the action of the elastic supporting apparatuses.

BRIEF DESCRIPTION OF THE DRAWING The invention will be described with reference to the accompanying drawing wherein:

FIG. I is a top schematic view of a portion of a prior art printer;

FIG. 2 illustrates the type-carrying belt of FIG. 1',

FIGS. 3 and 4 are schematic views of two embodiments of the invention;

FIGS. 5 and 6 are respectively top and elevational views of a supporting apparatus for the intermediate members;

FIG. 7 is an elevational view of a variation of the intermediate members supporting apparatus;

FIG. 8 is a cross-sectional view taken along line VIII- -VIII of FIG. 7; and

FIG. 9 is a partial perspective view of the supporting apparatus of FIGS. 7 and 8.

In these figures, the same reference numerals designate similar elements.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The portion of the prior art printer shown schematically in FIG. 1 comprises a plurality of striking hammers l, which are aligned and disposed at fixed positions. As shown in FIGS. 3 and 4, these hammers may be attached to actuators 2 which are supported relative to frame 3 of the printer by two leaf springs 4 and 5. Springs 4 and 5 are crossed so that the hammers can be displaced (arrows F in the direction of a character support belt 6 and a print-receiving means 7. The actuators 2, which comprise, for example, windings disposed in a magnetic field, are displaced electrically in the direction of arrow F and elastically in the opposite direction (arrows F under the action of springs 4 and 5.

The character support belt 6 is formed by a flexible and elastic band comprising transverse fingers 8. Characters 9 are affixed to the free ends of fingers 8. Belt 6 moves at high speed in the direction of arrow F which is perpendicular to the direction of arrows F and F At the same time, print-receiving means 7, for example a web of paper, can be displaced in the direction of arrow F (FIG. 3).

When a character is to be printed, a hammer l is actuated (see FIG. I) in order to assume the position I, at which the actuated hammer presses print-receiving means 7 against character support belt 6. In this position l the actuated hammer I undergoes a lateral impulse (in the direction of arrow F as a consequence of the contact made with belt 6. This lateral impulse has the effect of inducing substantial disturbances in the operation.

In order to remedy this defect, the printer of the invention, which is shown in FIGS. 3 and 4, comprises intermediate members 10 disposed between hammers l and belt 6. One member 10 is associated with each hammer 1. Accordingly, it is the members I which receive the lateral impulse at the moment of printing.

Members 10 are attached to the ends of respective elastic leafs I], and the other ends of leafs 11 are affixed to frame 3. Leafs l1 normally maintain members 10 separated from characters 9. When a printing is to occur, a hammer l urges its associated member 10 against the action of the corresponding leaf 11.

If the hammers l are very closely spaced, it is necessary to prevent leafs 11 from being too narrow, otherwise their strength would be too weak. In such instance, leafs II are provided with a greater width toward the edge of frame 3 than at the end of attachment of members 10 (see FIGS. and 6). However, these leafs 11 are slightly twisted in order that the enlarged ends of adjacent leafs can be overlapped obliquely relative to the direction of motion of hammers 1, while the members all lie in the same plane. Clearly, if it is not imperative (particularly with respect to the effects on the striking) that all members 10 lie in the same plane, it is not necessary to twist leafs 11. It is then adequate to dispose the latter at different levels.

In FIG. 6, leafs II have been shown to be of trapezoidal form. but it is apparent that their form may differ. The principle involved is that when a member 10 is urged in the direction of a character 9, its motion must not be hindered by leafs II which surround the members path.

In the embodiment of FIG. 3, the mass of a member 10 is negligible relative to that of a hammer 1. In this embodiment, the members I0 are continually held against hammers l by leafs 11 and they form only a part of such hammers.

On the other hand, in the embodiment of FIG. 4, the mass of a member 10 is less than that of a hammer I, but it is not negligible relative thereto. In this embodiment, the members 10 serve the hammers l properly by being placed into motion by the energy of the hammers transferred thereto at the time of their impacting with members 10. Members 10 are therefore normally held separated from hammers 1 by elastic leafs 11 in this embodiment.

As has been mentioned above, it is indispensible that the critical frequency of the pair consisting of a member 10 and leaf ll be greater than that of a hammer. Accordingly, preferably, leafs 11 are of titanium.

FIGS. 7, 8 and 9 illustrate a preferred embodiment of a supporting apparatus for intermediate members 10. An elastic leaf l2 and an elastic leaf 13 are disposed on opposite sides of a member 10. The length of leafs l2 and I3 is substantially perpendicular to the direction of displacement of members 10. Leafs l2 and 13 hold a member 10 between their free ends and 13a.

The leafs l2 and 13 associated with a particular member 10 are shaped so that angled middle portions 12d and 13d extend in opposite directions and spaced apart, preferably symmetrically with respect to the longitudinal axes of ends 12a and 13a. In addition, the middle portions 12c and are coplanar.

The legs 12b of all leafs 12 are attached to a band 14, which is affixed, in turn, to frame 3. The legs 13b of all leafs 13 are attached to a band 15, similarly affixed, to frame 3.

The assemblages of leafs l2 and band 14 and of leafs l3 and band 15 can be obtained by cutting from and forming an elastic metallic strip. These two assemblages are then inverted by relative to one another.

Accordingly, there is obtained a supporting apparatus for intermediate members 10, which is simple, economical and effective. Leafs 12 and 13 may be of titanium, as has been described for leafs 11.

Much that has been described in the foregoing and that is represented in the drawing is characteristic of the invention. It is evident that one skilled in the art is able to adduce all modifications of form and of detail using his judgement, without departing from the scope of this invention.

What is claimed is:

l. A printer comprising:

a plurality of print characters linearly supported on a moveable belt, said belt being moveable in a first direction parallel to a print receiving means;

a plurality of flexibly mounted print hammers for driving said linearly supported print characters in a second direction toward said print receiving means, said second direction being perpendicular to the first direction of motion of the print characters, each of said flexibly mounted print hammers being mounted at one end ofa leaf spring. the other end of said leaf spring being fixedly attached to the frame of said printer.

a plurality of print hammer actuating means for moving said print hammers in said second direction; and

a plurality of intermediate members. each of which is disposed between one of said print hammers and said print characters.

means for resiliently mounting said intermediate members to the frame of said printer for movement under the action of said print hammers in said second direction only between said print hammers and said print characters, the arrangement of the intermediate member between one of said print hammers and said print characters being such as to prevent any lateral displacement in said first direction of any print hammer when said means for resiliently mounting said intermediate members to the frame of said printer comprises pairs of elastic leafs wherein each of said intermediate members is held between the free ends of a pair of elastic leafs, the length of said elastic leafs being substantially perpendicular to the direction of motion of said memher. and wherein the other ends of said leafs are attached to the frame of said printer; and

wherein each of said pair of leafs associated with a particular member comprise two end portions and an angled middle portion. wherein the angled middle portion of a leaf attaching to one side of an intermediate member extends in an opposite direction relative to the middle portion of the leaf attaching t0 the opposite side of the intermediate member. and said end portions which fixedly attach to the frame are spaced apart by the amount by which said angled middle portions extend in opposite directions.

2. The printer of claim 1 wherein each of said plurality of elastic leafs upon which said intermediate members are mounted comprise a free end upon which an intermediate member is mounted and a fixed end fixedly attached to the frame of said printer.

3. The printer of claim 1 wherein the angled middle portions of each of the leafs attaching to one particular side of their respective intermediate members all extend in the same direction and the end portions of the leafs attaching to one particular side of their respective members all are commonly attached to the frame of the printer.

4. The printer of claim 3 wherein each of said leafs further comprises second middle portions, said second middle portions extending downwardly from the angled middle portions. and being coplanar with each other.

5. A printer comprising:

a plurality of print characters linearly supported on a moveable belt, said belt being moveable in a first direction parallel to a print receiving means; a plurality of flexibly mounted print hammers for driving said linearly supported print characters in a second direction toward said print receiving means. said second direction being perpendicular to the first direction of motion of the print characters; each of said flexibly mounted print hammers being mounted at one end of a leaf spring. the other end of said leaf spring being fixedly attached to the frame of said printer;

a plurality of print hammer actuating means for moving said print hammers in said second direction;

and

plurality of intermediate members. each of which is disposed between one of said print hammers and said print characters.

means for resiliently mounting said intermediate members to the frame of said printer for movement under the action of said print hammers in said second direction only between said print hammers and said print characters. the arrangement of the intermediate member between one of said print hammers and said print characters being such as to prevent any lateral displacement in said first direction of any print hammer when actuated, and wherein said means for resiliently mounting each of said intermediate members comprises a plurality of elas tic leafs upon which said plurality of intermediate members are mounted, the lengths of each of said elastic leafs being substantially perpendicular to the direction of motion of said intermediate mem' bers, each elastic leaf being fixedly attached to the frame of said printer and being wider at the ends thereof attached to said frame than at the ends on which said members are mounted. and

wherein each of said elastic leafs upon which an intermediate member is mounted is tapered outwardly from the end upon which the intermediate member is mounted to the end which is fixedly attached to said frame and wherein each of the ends of the tapered elastic leafs which are fixedly attached to said frame overlap the immediately adjacent fixedly attached ends of adjacent tapered elastic leafs.

6. The printer of claim 5, wherein said leafs upon which said intermediate members are mounted are twisted and wherein their overlapping ends are oblique relative to the direction of motion of said hammers.

7. The printer of claim 5, wherein the pair of leafs associated with a particular intermediate member are shaped so that their ends attached to said frame 8. The printer of claim 7, wherein the middle portions of the two leafs associated with a particular intermediate member are coplanar.

9. The printer of claim 5, wherein said leafs upon which said intermediate members are mounted are of titanium.

DATED [SEAL] PATENT NO.

INVENTORIS) It IS CEIUIIEU the! east appears In the ahove-ldenttfied patent and that salt; Letters Patent are hereny catrected 3s sham beiow:

UNITED STATES PA'IEN'I OFFICE CERTIFICATE OF CORRECTION 3,893,390 July 8, 1975 Jacques Roland Deproux Claim 7, line 50, after "frame" A nest:

insert --are spaced apart."

Signed and SeaIcd this thirtieth Day Of September1975 C, MARSHALL DANN Commimoner of Parents and 'I'rudrmarkv 

1. A printer comprising: a plurality of print characters linearly supported on a moveable belt, said belt being moveable in a first direction parallel to a print receiving means; a plurality of flexibly mounted print hammers for driving said linearly supported print characters in a second direction toward said print receiving means, said second direction being perpendicular to the first direction of motion of the print characters, each of said flexibly mounted print hammers being mounted at one end of a leaf spring, the other end of said leaf spring being fixedly attached to the frame of said printer, a plurality of print hammer actuating means for moving said print hammers in said second direction; and a plurality of intermediate members, each of which is disposed between one of said print hammers and said print characters, means for resiliently mounting said intermediate members to the frame of said printer for movement under the action of said print hammers in said second direction only between said print hammers and said print characters, the arrangement of the intermediate member between one of said print hammers and said print characters being such as to prevent any lateral displacement in said first direction of any print hammer when said means for resiliently mounting said intermediate members to the frame of said printer comprises pairs of elastic leafs wherein each of said intermediate members is held between the free ends of a pair of elastic leafs, the length of said elastic leafs being substantially perpendicular to the direction of motion of said member, and wherein the other ends of said leafs are attached to the frame of said printer; and wherein each of said pair of leafs associated with a particular member comprise two end portions and an angled middle portion, wherein the angled middle portion of a leaf attaching to one side of an intermediate member extends in an opposite direction relative to the middle portion of the leaf attaching to the opposite side of the intermediate member, and said end portions which fixedly attach to the frame are spaced apaRt by the amount by which said angled middle portions extend in opposite directions.
 2. The printer of claim 1 wherein each of said plurality of elastic leafs upon which said intermediate members are mounted comprise a free end upon which an intermediate member is mounted and a fixed end fixedly attached to the frame of said printer.
 3. The printer of claim 1 wherein the angled middle portions of each of the leafs attaching to one particular side of their respective intermediate members all extend in the same direction and the end portions of the leafs attaching to one particular side of their respective members all are commonly attached to the frame of the printer.
 4. The printer of claim 3 wherein each of said leafs further comprises second middle portions, said second middle portions extending downwardly from the angled middle portions, and being coplanar with each other.
 5. A printer comprising: a plurality of print characters linearly supported on a moveable belt, said belt being moveable in a first direction parallel to a print receiving means; a plurality of flexibly mounted print hammers for driving said linearly supported print characters in a second direction toward said print receiving means, said second direction being perpendicular to the first direction of motion of the print characters; each of said flexibly mounted print hammers being mounted at one end of a leaf spring, the other end of said leaf spring being fixedly attached to the frame of said printer; a plurality of print hammer actuating means for moving said print hammers in said second direction; and a plurality of intermediate members, each of which is disposed between one of said print hammers and said print characters, means for resiliently mounting said intermediate members to the frame of said printer for movement under the action of said print hammers in said second direction only between said print hammers and said print characters, the arrangement of the intermediate member between one of said print hammers and said print characters being such as to prevent any lateral displacement in said first direction of any print hammer when actuated, and wherein said means for resiliently mounting each of said intermediate members comprises a plurality of elastic leafs upon which said plurality of intermediate members are mounted, the lengths of each of said elastic leafs being substantially perpendicular to the direction of motion of said intermediate members, each elastic leaf being fixedly attached to the frame of said printer and being wider at the ends thereof attached to said frame than at the ends on which said members are mounted, and wherein each of said elastic leafs upon which an intermediate member is mounted is tapered outwardly from the end upon which the intermediate member is mounted to the end which is fixedly attached to said frame and wherein each of the ends of the tapered elastic leafs which are fixedly attached to said frame overlap the immediately adjacent fixedly attached ends of adjacent tapered elastic leafs.
 6. The printer of claim 5, wherein said leafs upon which said intermediate members are mounted are twisted and wherein their overlapping ends are oblique relative to the direction of motion of said hammers.
 7. The printer of claim 5, wherein the pair of leafs associated with a particular intermediate member are shaped so that their ends attached to said frame
 8. The printer of claim 7, wherein the middle portions of the two leafs associated with a particular intermediate member are coplanar.
 9. The printer of claim 5, wherein said leafs upon which said intermediate members are mounted are of titanium. 